Network virtualization is a technical hotspot, and is also the development trend of future network. A physical network can be shared by multiple operators, which can increase the utilization rate of the network. There is some related work in access networks. E.g. the broadband forum (http://www.broadband-forum.org/) has defined a L2 wholesale mode and a L3 wholesale mode, which allows the operator of an access infrastructure network (AIN) (i.e. the operator of a fixed access network) to rent some bandwidth resources of the access network to the third part except users and the operator of the access infrastructure network, e.g. a virtual network operator and a service provider. Another example, the open light-wave initiator established in 2010 (http://www.openlambdainitiative.org/Website/Home.aspx) also describes an open architecture framework, which evolves from the existing closed network to an open service model, and arouses the attention of the emerging technology from the industry. “New or alternative operators need an unlimited way which make their own technical platform to obtain unrestricted access to the existing city access architecture, thereby, they can focus on the content service of end users, and the performance requirement of the data link layer, while will not repeat the construction of an access structure”. The new or alternative operators referred herein are the virtual network operators mentioned above, and they need to rent physical access network resources to provide their own business/service to users.